The present invention is employed in a printing machine which employs the basic reprographic process used in an electrostatographic printing machine which generally involves an initial step of charging a photoconductive member to a substantially uniform potential. The charged surface of the photoconductive member is thereafter exposed with light in an imagewise manner to selectively dissipate the charge thereon in selected areas irradiated by the light image. This procedure records an electrostatic latent image on the photoconductive member corresponding to the informational areas contained within the original document being reproduced. In a printing machine using liquid electrophoretic developer the latent image is then developed by bringing a liquid developer material including toner particles which pass by electrophoresis into contact with the latent image. The toner particles form a toner image on the photoconductive member which toned image is subsequently transferred to a copy sheet.
It is highly desirable to increase the process speed and to reduce the size of a developer apparatus. This would enable a more compact and higher copy output printing machine.